The New Delhi office was set up during 1949 as the AMD headquarter, which was shifted to Hyderabad in 1974 and the office at New Delhi remained as the regional headquarter for Northern Region. Rajasthan was initially a part of the Northern Region, but during 1988 it was included in the newly created North-western Region. (Now Western Region).
Northern Region covers the states of Uttar Pradesh, Uttarakhand, Himachal Pradesh, Jammu & Kashmir, Ladakh, Haryana, Punjab and parts of Madhya Pradesh and Rajasthan. The Region comprises of the Great Himalayan mountain ranges exposing igneous and metasedimentary rocks of various ages in the Higher and Lesser Himalayas, the Tethys-Himalaya and Tertiary sediments, the vast Indo-Gangetic alluvial tracts and the Archaean granitoids and Proterozoic sediments in the south. The Main Central Thrust (MCT) separates the Higher Himalaya from the Lesser Himalaya. The Higher Himalayas comprises of granite gneisses and high grade metamorphic rocks (Central Crystalline axis). To the south, across MCT, the Lesser Himalayas are represented by metasedimentary and metabasic rocks with some well-known nappes and klippes, with or without intrusive granites. The Main Boundary Thrust (MBT) separates the Lesser Himalayan rocks from Tertiary sedimentary belt. The Siwalik sediments extends from Jammu & Kashmir through Himachal Pradesh to Uttarakhand. The intracratonic Himalayan Frontal Thrust (HFT) to the south separates the Siwaliks from the Indo-Gangetic plains. Further south of the Indo-Gangetic plain, the Proterozoic intracratonic Bijawar - Gwalior - Vindhyan basins overlie the Bundelkhand Granite Complex (BGC). The southern margin of the Vindhyan Basin is bounded by the Mahakoshal Group and Chhotanagpur Granite Gneiss Complex (CGGC). The north-eastern parts of North Delhi Fold Belt (NDFB) comprising metasediments of Delhi Supergroup in parts of Haryana and Rajasthan is another important geological domain covered under the Northern Region.
The geological framework hold potential for hosting diverse type of uranium deposits and sustained exploration efforts have resulted in delineation of several promising uranium occurrences viz. Naktu, Sonbhadra district, Uttar Pradesh; Pokhri-Tunji, Rudraprayag, Uttarakhand; Kasha-Kaladi, Shimla, Himachal Pradesh (metamorphite type) and Tileli, Mandi district and Rajpura, Una district, Himachal Pradesh (sandstone type).
Proterozoic unconformity type uranium occurrences have been located at the unconformity contact between the Proterozoic cover rocks (Vindhyan/Gwalior) and Bundelkhand Granite Complex (BGC) in Doha, Dursendi and Maharampur areas of Gwalior district, Madhya Pradesh.
Metamorphite type uranium occurrences have been established in many places in Sonbhadra district of Uttar Pradesh, such as Naktu, Kudar, Anjangira, Kudri, Satbahni-Murratola and Nawatola areas. The host rock is mostly feldspar rich Pegmatoidal Leucosome (PL) and to a lesser extent, Biotite Melanosome (BM), both comprise the prominent proportion of the migmatites of Chhotanagpur Granite Gneiss Complex (CGGC). Besides, uranium mineralisation associated with fracture-filled bitumen in chloritic shale, Bandai Sandstone and Rohini Carbonate of Bijawar Group is located around Sonrai, Lalitpur district, Uttar Pradesh.
Significant metamorphite-type uranium mineralisation has been located in the sheared gneisses and quartzites of the Rampur Group along Main Central Thrust (MCT) in the Higher Himalayas at Chaura, Kinnaur district and Kasha - Kandi – Kaladi, Shimla district of Himachal Pradesh. Yellow cake has been obtained from uraninite veins (veinlets) of Kandi area by small scale mining and heap leaching. Similar uranium occurrences have also been located in Berinag Quartzite of Uttarakhand. Shear/fracture - controlled uranium mineralisation of significant dimensions and grades is hosted by chlorite-sericite schists in Pokhri area of Chamoli district and in granite gneiss in Brijranigad area of Tehri district of Uttarakhand.
Metasomatite type uranium mineralisation is identified in albitites of north-eastern parts of North Delhi Fold Belt (NDFB) in Dochana, Mohanpur and Rambas areas, Mahendragarh district, Haryana and Jhunjhunu district, Rajasthan.
Sandstone type uranium occurrences have been located in the pre-Siwalik Tertiary sediments of Dharamsala Group of rocks in Solan and Mandi Districts, Himachal Pradesh, out of which Tileli is the most prominent occurrence identified so far. At Tileli, uranium mineralisation is associated with lithic arenites at the contact of Lower and Upper Dharamsala Formations, was delineated over a zone of 500m x 10m and up to a vertical depth of 300m. The Siwalik sediments due to their sedimentological character, provenance and depositional environment have been considered as favourable host for epigenetic sandstone-type of uranium mineralisation. Investigations carried out by AMD since 1969 in different phases, have resulted in discovery of many uranium occurrences from Jammu & Kashmir in the northwest to Uttar Pradesh and Uttarakhand in the south-east. Lenticular uraniferous zones extending from tens to hundreds of metres in dimension with low average grade have been found over large areas in both sandstone and conglomerate in the Upper-Middle Siwalik transition zones of Himachal Pradesh, Uttarakhand and Jammu and Kashmir. Exploratory mining was done in three blocks viz. Astotha, Khya and Andalada in Hamirpur district, Himachal Pradesh. Important uranium occurrences established are Rajpura, Una district and Loharkar, Hamirpur district in Himachal Pradesh; Danaur and Naugajia Rao-Shakambari Rao, Saharanpur district, Uttarakhand; Maler and Thein, Kathua district, Jammu & Kashmir; Morni, Panchkula district, Haryana.
Phosphorite / black shale types occurrences have been located in Lower Tal Formation near Krol-Tal contact along the potential inner Krol belt (Nigalidhar, Mussoorie and Garhwal synclines) of Lesser Himalaya. Besides, occurences of Black shale type uranium mineralisation hosted by carbonaceous shales of Haimanta Group in Tethyan zone is identified.